Engine-starter.



V. BENDIX.

ENGINE STARTER.

APPLICATION FILED Aue.|4. 191s.

Patented Aug. 6, 1918.

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VINCENT BENDIX, OF CHICAGO, ILLINOIS.

GINE-STARTER.

Specification of Letters Patent.

Application filed August 14, 1916. Serial No. 114,896.

1 To all whom it may concern:

Be it known that I, VINCENT BENnIx, a citizen of the United States, residing at Chi; cago, in the county of Cookand State of Illinois, have inventedcertain new and useful Improvements in Engine- Starters, of which the following is a specification.

My invention relates to that type of en gine starter exemplified in patents heretofore issued to me, for instance Patent No. 1,146,992, issued on July 20, 1915, which starter is characterized by a prime mover such as an electric motor, and a transmission or drive for transmitting the power or motion of the motor by means of a screw shaft device to a member of the engine, such as the fly wheel thereof. This transmission or drive comprises a screw shaft operated either directly or indirectly by the electric motor and adriving member such as a pinion mounted on such shaft for longitudi nal movement thereon and rotary movement therewith. My invention pertains more particularly to the construction of this pinion, and the object thereof is to improve the action thereof on the screw shaft, particularly that action which takes place after the engine has started onits own power and has automatically demeshed the pinion from the fly wheel.

. In the automatic demeshing of the pinion from the fly wheel the pinion, after moving l'on 'tudinally on the screw shaft in this demes ing operation, pauses or sto s momen- 86 tarily after having cleared the ace of the fly wheel a slight distance and rotates with the screw shaft until sue shaft has slowed down, whereupon the pingon will travel lon- 'tudinally to home position along the screw liaft, but with slight force. This peculiar cooperation betweenjthepinion and screwshaft also has the efl'ect of holding the pinion towardits retracted or home position, and tends to prevent its advance movement against the fly-wheel in the event, after the engine has started on "its own power, the

armature shaft of the electric motor should continue to be rotated rapidly due to inadvertently keeping the current closed on the. motor. This pausing or momentary stopping of the pinion on the screw-shaft is due to a binding effect between the threads 7 of the-shaft and pinion due to the centrif ugal action of the weight arranged at one end of the pinion and projecting from one side of a vertical plane passing through the point of support of such weight and pinion with respect to the screw-shaft, the'centrifugal action tending to draw the weight in a plane of rotation coincident with said vertiin Figure l by the dotted line a-a, and the outer plane by the dotted line bb. The object of the present invention .is to obtain the proper or correct binding effect of thepinion on the screw-shaft which is done by the construction and relationship of pinion and weight as hereinafter described. Speaking in general terms, I accomplish this object,

in the broader aspect of my invention, by

locating the weight at one end of the pinion,

being the end opposite the end which initially meshes with the engine memberby terminating the internal threads of the pinion short of the inner side thereof, that is, the end on which the weight is mounted, thereby providing an unthreaded ortion in the bore of'the pinion which over angs the shaft so that the point of support of the weight end of the pinion with respecttothe of the weight by increasing the counterbore.v

In the drawing, Fig. 1,'is an elevation partly in section of a transmission or drive embodying my invention, and Fig. 2 a central longitudinal section of the pinion.

Inasmuch as my invention concerns only the transmission or drive of an engine starter, which may be operated either directly or indirectly by any prime mover, such as an electric motor, I have shown merely such drive, with the exception that I have shown in addition the extended armature shaft 1 of an electric motor as in the case of a direct drive between the prime mover and this transmission. The armature shaft.1, is secured by means of a bolt 1 to the driving member or collar 2, which is operatively connected by means of the coiled spring 3 with a driving collar 49, which is preferably an integral part of the screwshaft. This screw-shaft is provided at its Patented Aug. 6, 191's.

cal plane. This vertical plane is represented the screw-shaft is mounted a driving memher, which is in the form of. a pinion 6, screw-threaded upon the screw-shaft by means of its internal threads 6 with the result that such pinion is capable of moving longitudinally on the screw-shaft, and also rotarily therewith. When the-pinionis ad- Vanced, that is, moved to the right in Fig. 1, it meshes With the teeth 7 of an engine member, such as the fly-wheel 7 of the engine to be started.

The pinion is provided at one end, which is the end opposite the end which meshes with the fly-Wheel, with a weight 8, which is here shown as forming a part of the disk 8*. In practice the weight constitutes a flange occupying one-half of the circumference of the disk and extending therefrom laterally and at right angles and consequently at right angles to the end of the pinion.

The bore of the pinion is provided with screw threads 6 for only a portion of its length, such threads stopping short of the weighted end of the pinion. As a result there is a portion of the bore at .6 which is not provided with threads, and which overhangs the screw-shaft, so that the first point of support of the pinion is at the first thread, as at 6, with the result that in its rotation, the weight 8 tendsto move into a plane of rotation coincident with a vertical plane passing through point 6, thereby causing a cooking of the pinion and a binding thereof on the screw-shaft. The proper action is obtained and controlled by a proper relation between the amount of the weight and the depth of the counterbore, such counterbore increasingthe centrifugal leverage on the cocking action of the pinion, and consequently the binding efiect thereof on the shaft.

ll claim:

1. In a drive for an engine starter, the

combination of a rotatable screw' member,

and a member screw threaded thereon and capable of longitudinal movement thereof and rotary movement therewith, said second mentioned member being weighted on one end and on one side of its axis of rotation and having screw threads for only a portion of its length.

2. lln a drive for an engine starter, the combination of a rotatable screw-shaft, and

p a member screw-threaded thereon and capanemes s tially through its bore, leaving the unthreaded portion at its weighted end.

3. In a drivefor an engine starter, the combination of a rotatablescrew-shaft, and a member screw-threaded thereon and capable of longitudinal movement thereof and rotary movement therewith, said member having at one end a weight arranged on one side of the aXis of rotation of such member and located on one side of a plane extending at right angles to the longitudinal axis of the Shaft and running through the point of support of the weight and said member on the shaft, whereby the centrifugal action of the weight in the rotation of said member tends to move the plane of rotation of such weight into a plane coincident with said lane passing through said point of support.

4. In a drive for an enginestarter, the combination of a rotatable screw-shaft, and a member screw-threaded thereon and capable of longitudinal movement thereof to engage a part of the engine to be started and capable of rotary movement therewith, said member being weighted at the end opposite its engaging end and having its internal screw-threads extending only partially through its bore, such threads stopping short of the weighted end of said member.

5. In a drive for an engine starter, the combination of a rotatable screw-shaft, and a pinion screw-threaded thereon and capable of longitudinal movement thereof and rotary movement therewith, said pinion having internal screw-threads extending only partially through its bore leaving an unthreaded portion at that end opposite its engaging end, said pinion also having a weight located at its opposite'end and arranged on one side of its axis of rotation.

6. In a drive for an engine starter, the combination of a rotatable screw-shaft. a pinion screw-threaded thereonand capable of longitudinal movement thereof to engage a member of the engine to be started. and capable of rotary movement therewith, said pinion having internal screw-threads extending only partially through its bore and stopping short of that end which is opposite the engaging end thereof, and a weight depending from that end of the pinion opposite it engaging end and arranged on one side of a plane located at right angles of the axis of rotation of the pinion and passingsubstantially through that end of the screwthread adjacent the weighted end of such pinion.

I VINCENT BENDTX. Witnesses:

S. E. HIBBEN,

Ronnn'r DOBBERMAN. 

